Questions tagged [supernova]
Questions regarding stars which increase suddenly in energy output due to an explosion which ejected much of its mass.
173
questions
0
votes
0answers
13 views
Calculating Relative Abundances to Solar For Explosive Nucleosynthesis Yields
I am having trouble deriving the abundance ratios for the ejecta products of a given supernova explosion model. From the explosion models, we are given the mass of 3 isotopes of every element produced ...
10
votes
6answers
6k views
Did I see a supernova explosion?
I think I just saw a supernova explode with my own eyes through my GSO 12 inch Dobsonian. Please tell me what it was! I am still trying to find what it was it was mindblowing!
I went out on my roof ...
3
votes
1answer
81 views
Would a naked eye supernova become a disc in a matter of days?
Stars are points of light even in telescopes- if they go supernova, their diameter does expand, but given the distance of even nearby stars, they would still be points of light, I suppose?
I am asking ...
2
votes
1answer
50 views
What does “located in the Hubble flow” mean?
I do not understand that much about the term Hubble flow.
For cosmological studies with type Ia supernova, I often see the sentence like "We used 100 SNe Ia in the Hubble flow". What does ...
5
votes
1answer
80 views
Why did supernova 1987A's “String of 'Cosmic Pearls'” appear to be so lumpy 20 years later? Is it still?
NASA's A String of 'Cosmic Pearls' surrounds an exploding star is beautiful and the page says:
This image shows the entire region around the supernova. The most prominent feature in the image is a ...
1
vote
2answers
29 views
How can I estimate the initial luminosity of a SNIa given initial mass of Ni-56?
The initial portion (and peak) of a SNIa's light curve is powered by the $\beta$-decay reaction:
$$ ^{56}Ni \rightarrow ^{56}Co + e^+ + \nu_e + \gamma $$
Supposing we know how much Ni-56 is created in ...
2
votes
1answer
69 views
At what distance could a supernova damage the Earth's ozone layer?
As from my latter question it seems Betelgeuse might be much closer than the usually presumed 640 light years. It might be as close as ~440 ly. Suppose it is, would this have any dangerous effects on ...
3
votes
1answer
41 views
Galactic winds/outflows: why and how are they detected via blueshifted absorption lines in spectra?
I know that galaxies can eject gas due to supernovae, accreting black holes, etc. These galactic "winds/outflows" are often defined/detected observationally using blueshifted absorption ...
20
votes
3answers
5k views
When was it worked out/discovered that our sun can't go supernova?
As the title says, when did we realise with reasonable confidence that our star is not going to be going out in a supernova blaze of glory?
I ask because a while ago I read The Songs of Distant Earth ...
0
votes
1answer
79 views
What happens when a huge star is being consumed by a black hole
What happens when a huge star in its later stage( iron core) is near a black hole that slowly consumes some of the matter from the star? Would this offset the imbalance caused by iron fusion ...
23
votes
1answer
2k views
Why are there so few supernovae in M31 (Andromeda)?
Estimates of the supernova rate in the Milky Way put it at a few per century, but very few of these are visible from Earth (at least with the naked eye) because of intervening gas and dust clouds). On ...
5
votes
0answers
83 views
How often are supernovas visible by the naked eye from Earth?
I heard about the 1054 supernova that was visible with the naked eye.
Of course, these events happen at random. But just like with radioactive decay, it must be possible to determine statistics on ...
-8
votes
6answers
333 views
any proof that stars are born, and die?
I've heard from a lot of people that stars are "born" (usually from black holes), then grow bigger, then eventually "die" by some kind of supernova etc., but have any of these events actually been ...
2
votes
2answers
76 views
What kind of radiation do supernova remnants emit?
Do supernova remnants emit EM radiation? Moreover can neutrinos be emitted by these remnants?
6
votes
2answers
119 views
Why do pair production and photodisintegration have such different effects in collapsing supermassive stars?
Stars of at least 100 solar masses or so can reach core temperatures (and, thus, core photon energies) great enough that pair production (where a very-high-energy photon strikes another particle, ...
29
votes
1answer
3k views
Why don’t supergiants at least start to fuse nickel into even heavier elements before going supernova?
The last primary fusion process to take place in extremely massive stars is silicon burning, where the 28Si produced by oxygen burning is exothermically fused with alpha particle after alpha particle ...
0
votes
0answers
30 views
How to derive the formula of magnitude error caused by peculiar velocity?
I want to understand how to derive the formula of magnitude error ($\sigma_m$) which is caused by peculiar velocity of a galaxy, like this
$$
\sigma_m = \frac{5\ \sigma_V}{cz\ \rm{ln(10)}}
$$
,where $\...
9
votes
1answer
207 views
Was the “green star” event in NGC 3314 ever figured out or named?
from NGC 3314 Variable Object by By Bill Keel (University of Alabama, Tuscaloosa) and Lisa Frattare (Hubble Heritage Project, STScI). The object in question is circled.
Comments below this answer led ...
20
votes
1answer
2k views
What causes fast moving pulsars to move so fast?
This article investigates the traces left in the ISM by fast moving pulsars. Is there a mechanism specific to pulsars that causes them to move so fast, or are there just as many fast moving stars?
...
0
votes
0answers
5 views
Do all High-Mass X-Ray Binaries have observable supernova remnants surrounding them?
I am studying high mass X-ray binaries, which are star systems that generally contain a neutron Star orbiting a larger companion. My assumption is that such systems began as two typical stars in ...
2
votes
1answer
125 views
How does a supernova occur when a massive star collapses into a black hole?
My layman's understanding of a supernova explosion is that it's caused by a rebound when a massive star collapses. When the core collapses to a point where neutron degeneracy pressure dominates, the ...
4
votes
1answer
212 views
When Betelgeuse goes supernova, will the explosion hit any neighboring stars?
There is evidence Betelgeuse might go supernova "soon". Are there any stars in the vicinity of Betelgeuse that are close enough that they will be hit by the explosion of this supernova? What would be ...
2
votes
0answers
52 views
How scientists estimated the number of near-Earth supernovae over the last 11 million years?
According to this article on wikipedia,
An estimated 20 supernova explosions have happened within 300 pc of
the Earth over ...
4
votes
2answers
186 views
Have we ever seen the formation of a blackhole?
So I know that the formation of a supernova has been observed and that we have taken images of blackholes, however, has the formation of a blackhole ever been observed. How do we observe it?
3
votes
0answers
57 views
How many galaxies have had their distance determined using SNIa?
Supernovae of type Ia can be used as standard candles to determine extra-galactic distances. But these event only occur (roughly) once every 200 years in any given galaxy and rapidly fade away. So to ...
17
votes
3answers
4k views
How often do supernovae occur?
Type Ia supernova are used as standard candles. But they also are transient events. This means that to determine the distance of a galaxy using supernovae, you have to wait for one to occur. How often ...
8
votes
1answer
289 views
Will the nebula of Betelgeuse be visible to the naked eye? How bright, how large, how soon, for how long?
When Betelgeuse goes core collapse supernova it will leave a supernova remnant. Will it become visible to the naked eye? If so, in what time frame will it be visible. Will it be star like from the ...
22
votes
1answer
2k views
Are stars expected to become dimmer before a supernova?
With the recent news about the "fainting" of Betelgeuse and the speculation that this might be a precursor to a supernova, I'm wondering if there is any theoretical/observational basis for this ...
8
votes
1answer
379 views
What would the effects on or around Earth if Betelgeuse went supernova?
There's been a lot of news lately about Betelgeuse possibly exploding sooner than perhaps was expected. Some examples:
Guinan, Edward F.; Wasatonic, Richard J.; Calderwood, Thomas J. (8 December 2019)...
21
votes
2answers
3k views
What observation can be expected on LIGO if any when Betelgeuse goes supernova?
What observation can be expected from the LIGO† gravitational wave observatory if any when Betelgeuse goes supernova?
Could we know that Betelgeuse has gone supernova before we see it light up our ...
2
votes
2answers
106 views
Why does the Supernova 2006cm give a very different value for the Hubble constant? Why doesn't it increase error bars for the Hubble constant?
The Supernova 2006cm has a redshift of 0.0153 which translates into a recession speed of 4600 km/s.
It has a distance modulus of 34.71 which translates into a luminosity distance of 87 Mpc.
This ...
1
vote
0answers
44 views
Element Abundance Related To Star Explosions [closed]
Sorry if this question is too basic, but as I learned about how supernovae are means of producing heavy elements I began to wonder "What would happen if stars didn't explode, i.e. undergo supernova"? ...
5
votes
1answer
206 views
Proxima as Supernova
Follow this question. If a star at the same distance from us as, say, Proxima Centauri had exploded as a Supernova 4 years ago (I know, it can't explode as supernova, let's say it can)...
How bright ...
2
votes
1answer
84 views
Why do we expect Type Ia Supernovae to be brighter in a decelerating Universe than what has been observed?
This seminal review paper in the PNAS by Robert P. Kirshner (https://www.pnas.org/content/96/8/4224) says the following:
If the universe had been decelerating—–in the way it would if it contained ...
3
votes
2answers
85 views
What kind of star would allow for life like our Sun/Earth and then go nova?
In the Star Trek Prime Universe, Star Trek: The Original Series, the home stars of the Fabrini, Platoans and Sarpeidons went nova, while in Star Trek: The Next Generation one of the stars in the ...
6
votes
1answer
406 views
Is the resulting light from a supernova a product of photons bouncing around in the Sun?
I was thinking about how photons formed in the centre of the Sun take quite a long time to exit the surface. And it occurred to me that at the end of a star's life (during a supernova, given that it's ...
11
votes
3answers
283 views
What do the fusing 'onion layers' of a pre-supernova star look like to scale?
I'm sure we've all seen the diagrams of various layers of element fusion from hydrogen to silicon in a star that's just about to go supernova.
(Picture from courses.lumenlearning.com)
I suspect ...
9
votes
6answers
3k views
Why does matter stay collapsed in the core, following a supernova explosion?
Following a supernova explosion a star may turn into a white dwarf, neutron star, black hole, or just a stellar dust & gas leftover.
Excluding the latter case, why and how does the star's core ...
1
vote
1answer
39 views
Estimating the abundance of type-Ia supernovae using magnitude limited survey
I would like to estimate the fraction of type-Ia supernovae in a magnitude limited survey (only including those supernovae that are brighter than a certain than a given fixed apparent magnitude).
I ...
3
votes
0answers
106 views
Assuming no light pollution, was “2C. 1406” ever visible to the naked eye?
Joseph Needham, in his Science and Civilisation in China Vol. III, claimed that there was an ancient record of a nova about three thousand years ago. As a result of private correspondences with a "Dr ...
3
votes
2answers
315 views
Can an Earth-like planet survive if our Sun went Supernova?
First, I would like to point out, yes, our sun does not have enough mass to be a candidate for Supernova, this is a scenario were our sun is though, and after the various life cycle stages of the sun ...
2
votes
1answer
135 views
Is there a standardized “Astronomical Alert” system?
“Who saw” the binary neutron star merger first? What was the sequence of events? (GRB/GW170817) highlights a particularly notable astronomical alert, but I am sure that there are alerts triggered by ...
1
vote
0answers
51 views
How are constraints on dark energy improved the most?
Today we have various data available from independent probes to constrain dark energy, i.e. its equation of state $w$. These include Type 1a supernovae, BAO, CMB, large-scale galaxy surveys, etc. Are ...
4
votes
3answers
316 views
Can a black hole “supernova”?
In layman terms:
nothing ever escapes the pull of a black hole, not even light
when a super massive star reaches the end of it's life you get a supernova
sometimes the "remains" of these stars can ...
2
votes
1answer
59 views
Astrophysics of Supernovae - Energy over Distance?
I need this for worldbuilding, but it is a physics question. I want to be able calculate the energy over distance from a hypernova of a variable star like Eta Carinae. Understanding what energy levels ...
1
vote
0answers
29 views
How to calculate the light energy of a supernova?
I have been given a distance, an average flux, and a time period. How do I find the light energy emitted over that time period?
0
votes
1answer
93 views
Could pure iron from a star make it to Earth?
Since iron is a stars waste could a star that goes Super nova eject pure iron to travel across the galaxy?
https://space.stackexchange.com/questions/35101/99-99-pure-iron-meteorite
0
votes
1answer
186 views
What happens if a black hole is produced inside another black hole?
Similar question here.
The question I linked got me thinking.
It is known that a black hole doesn't let anything escape its event horizon, not even light. Thus, naturally, anything that passes the ...
-1
votes
1answer
166 views
What would happen if a star went supernova inside a supermassive black hole? [closed]
A black hole swallows a star.
The star remains intact.
Then goes supernova.
What would happen to the star?
Could we detect this event?
4
votes
2answers
125 views
Scientifically important discoveries with the help of amateurs
I am looking for examples where amateur astronomers in these days contributed sigificantly to important scientifically discoveries.
I am aware of one example: Victor Buso from Argentina was lucky ...
